This invention relates to a compact protector which is used to prevent excessive heating of a compact motor or the like that is used in heat generating appliances such as a hair dryer, a dish dryer, and the like, or in electric washing machine, an electric shutter, and the like. More particularly, the present invention relates to a protector with built-in double safety means which opens an electric path when an excess current and the rise of an ambient temperature take place. The protector of the present invention can prevent both the excess current and the excessive rise of temperature, and can accurately set its operating temperature.